In the present study we analyze the biomechanical properties of life-form parenchyma, derive the relationship between MR displacement-phase image and the elasticity of life-form parenchyma, thereby study the local frequency estimation(LFE) algorithm. Finally the algorithm is relized by Matlab, and the inversion results of phantom MRE image demonstrate the effectiveness of the LFE algorithm, which would form a basis for subsequent research on liver fibrosis classification .